Vintage Detecting Forum

Now when is is a detector like the Nautilus DMC going to become vintage ?

Manufactured until a few months back but remaining essential unchanged for years except for changes to the shaft design. Now one of the greatest machines made according to those that have them... pity they never managed to post many finds which might have led to more sales and company expansion. Not to much interest when I use to demonstrate them at rallies over the years and the Nautilus Club never got above twenty members !
One result is that a rather battered looking coil for sale at

Wonder if any one will buy the company and build them again didn't know they went out. I think if they would have changed things around a little (control box) maybe things would have been different. I've used them some had 3 but here in sw Missouri the ground is hot and they didn't seem that deep due to minerals here.Were really smooth tho. shortribs.

I just returned a Nauty type machine with all the mods we asked for for years. Lightweight, just over two and a half pounds compared to nearly 5 pounds. Battery check. Rechargables (charged through the headphone socket as per many of Eric Fosters pulse machines). More depth. Higher coil voltage. Frequency adjust to cope with power lines/EMI.

Unfortunately, though better on wet sand than the Tyndall designs, wet salt, as with most single frequency detectors, remains a weak point.

QuoteUK Brian
I just returned a Nauty type machine with all the mods we asked for for years. Lightweight, just over two and a half pounds compared to nearly 5 pounds. Battery check. Rechargables (charged through the headphone socket as per many of Eric Fosters pulse machines). More depth. Higher coil voltage. Frequency adjust to cope with power lines/EMI.
Unfortunately, though better on wet sand than the Tyndall designs, wet salt, as with most single frequency detectors, remains a weak point.

For those of us who've never used, nor seen one in action: What made the Nautilus so loved? Did it go any deeper than today's power-houses? TID better? Target separation better? Or just plain sounds were pleasant (yet perhaps not deeper than others), or ..... ? What ?

If you had the right ground the DMC (Dual Mode Circuit) Nautilus was and still is a deep machine partly because the primary search mode is all metal so doesn't suffer from the many drawbacks of discrimination. You hear everything but without the drawbacks you might expect. This is partly because the non motion all metal mode is so smooth and easy to listen to and partly because the motion discrimination mode operates at the same time without affecting the depth of the primary detecting mode.

Unlike say Spectrum or XLT which also have mixed mode options the DMC feeds all metal audio to one earpiece and the discrimination signal to the other. Always seems a lot less noisy than other methods and has the further advantage that targets can be identified by the way the two signals are presented to you in your headphones, ie do they come in together, or one louder than the other, matching or not matching audio strength etc.etc.

Add that instead of the limitation of the average machine running only a few volts through the coil, you can adjust "transmit power" to provide as much as 44 volts from the four 9 volt PP3 batteries. There's also two sensitivity controls, one for the motion side, the other for the non motion side allowing you to set the correct amount of receiver gain for each which is better than the one gain of most machines.

A further unique ability is that of search loop balance. Hot or cold conditions upset the architecture of all coils. The DMC IIB has a switch that brings two knobs into use. One adjusts Capacitance and the other the Resistance of the searchcoil windings which helps maintain maximum depth in varying conditions.

Operating Frequency 14 kHz. Six, eight, ten and fifteen inch coils (triaxle concentric) of two types....Low-Q (designed to deal with heavier concentrations of iron minerals) and High-Q (which detect deeper in lower mineral conditions).
All metal contruction. Auto tune that can be switched on or off. TR discrimination switch. Mixed mode can be switched off if required.
Batteries can be charged "on board".

Bad news....not being made since the company owner died. Repair situation iffy at present. Coils of later machines seem more fragile than the older/heavier ones of the original machines. Weight, the original versions with a sort of S shaped shaft feel a lot heavier at 4lbs 14oz than the recent Whites straight shaft models.

Nearly forgot. No DD coils so target seperation not as good as it could be. Doesn't cope with very high mineralisation. Though it has a TR mode it can't keep up with twin/multifrequency detectors on wet salt.

QuoteUK Brian ..... the motion discrimination mode operates at the same time without affecting the depth of the primary detecting mode .....

Brian, yes, thanx for taking the time to type that out. However, via what you said in the quote above: You're not trying to say that it's acheiving all-metal depths WHILE discriminating, are you ?

Simply because the machine can have the two modes over-lapping (which isn't "new" to a whole host of machines out there on the market), doesn't mean that your disc. depth has now magically stepped up to tha of all-metal depths. Because there will always be another 5% or 10% of depth that all-metal affords you, while the disc. depth will be slightly less than that.

A lot of folks have been misled to believe that they are getting the best of both worlds, simply because they're running concurrent. But this is not the case.

A lot of detectors have had an audible threshold in disc mode, but the Nautilus is the only detector I'm aware of that has a full fledged all metal and disc modes running at the same time. As Brian said, the all metal mode is heard in one ear and the disc mode in the other ear. I only used one a couple of times, but have seen targets dug at unbelievable depths by hunting buddies using them in the mild ground here. No way can anyone who hasn't used a Naughty make an accurate assessment of them. Link is to an article on my website about Nautilus detectors. It was written by Jbird and has a lot of interesting info in it.

Yes, I have no doubt that the 2 modes run at the same time (in different ears). That's not the point though. The point I'm making is that .......... just as in all machines: all-metal depth affords a bit more depth than disc. depth. So for example: If the max that a dime can be heard on that machine, in disc. mode is 10". Then it's possible that if the dime were at 11", then you might hear it in the ear which is all-metal, while NOT hearing it , in the disc. ear.

Not sure if that's clearly stated on my end.

Oh, and a clarification on this: For machines which have the 2 modes concurrently running (whether in separate ears, or in same ears), these "mixed" modes DO seem to give more depth, while discriminating, than if the user had been is *only* disc. mode. The reason for this is that since the all-metal portion of the signal is hearing the fainter/deeper signals, that the user tends to be "drawn" to investigate more targets. You know, the human nature of try to "scrub" or "criss-cross" or "center better", etc... over faint targets, to see if he can "bring them in". Whereas if he had been hunting in strictly discriminate mode, he might not have been alerted to fringe targets, to begin with. Is this making sense ?

You are drawn to investigate more targets which is the point. Then you can investigate with a different sweep speed,different directions of sweep, or an increasing/decreasing speed whatever works better for you to correctly I.D. the target. With a standard detector design you don't get the opportunity to investigate the extreme depth signals because you just don't hear them.....at best you can double check "iffy" signals but thats not really good enough.

Living in Europe for years I had the choice of using the semi-similar all metal primary search mode with discrimination by meter detectors from C-Scope, Saxon, Arado etc but that system comes up a little short as you have meter drift to cope with and the sheer fact of having to watch a meter whilst swinging the machine.

The G.N.R.S. relic hunt gives an indication of the performance of different brands of detectors and Nautilus would win repeatedly. Even now with new machines and coils not being sold and difficulties getting repairs, Nautilus has only dropped to sixth (still in front of Tesoro and Whites), Not bad for a twenty year old design !

Great machines. I dug some fine stuff with mine in the MS. woods. I loved the Dual mode it had, one side youd hear a high tone and one side low for iron. The first 2 tone machine I guess and this was back in the early 90's.

How about the Mikron NRG-110 or the Tesoro Tejon with the 12" DD coil? 15" (roughly) on a quarter. The Mikron can (for a rough estimation for depth of course), detect a nickel 16" away from the coil. And don't forget the Fisher F-75 Limited Edition. If one (really) wants deep, the Nexus Credo/ Standard SE/ Standard MP or a Minelab GPX4500 or 5000 can go as deep as 30" + on single coins.

The Nautilus has the sweetest audio once you learn it's language. It is called a Dual Mode Circuit, All metal,Disc/,But it actually has 3 seperate Target Tones to listen for. All metal tone,All metal and Disc. mode together,and Disc. only for the deeper Targets. And once you learn those there is a soft All Metal Tone for the deepest targets. You get the last one dig out some ground to see if you get a Soft Disc. Tone. If you do get ready to do some serious diggin' because it is deep. I just bought a NOS IIBa myself. It is my Third IIBa and fifth Nautilus detector as the Tones are just too addicting!